Turbine-wheel construction.



A UNITED STATES Patented' January 31, 1905.

PATENT OFFICE. s

RICHARD H. RICE, `OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEVVYORK.

ATURBINE-WHEl-:L CONSTRUCTION.

SPECIFICATION forming partof Letters Patent No. 7S1,22dated January 31, 1905.

` Appiianon tied July 22, 1904. sarai no. 217,677.

To all whom it may. concern.'

vRe it known that I, RICHARD H. RICE, a citizen of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Turbine-Wheel Constructions, of which the following isa specilication.

It has been demonstrated that large wheels as commonly constructed and used in elasticliuid turbines `have al tendency to warp or change their shape, due `to unequal temperaturesfon 'opposite sides. As a rule the inlet side of the wheel expands to a greater extent than the exhaust side, and this'frequently causes rubbing between the relatively rotating parts.

The object of my invention is to provide a wheel of improved construction wherein the temperature effects can be disregarded wholly or at least inlarge part.

In carrying out my invention a composite wheel is providedV comprising a central portion, which is of rugged construction, and detachable portions, which are suitably attached to the central portion.. The central and detaehableportions 'are so united that they are capable of having a slight movement with respect to each other in a radial direction, the object of this vbeing to permit one portion to expand or contract without affect-` ing another portion or portions. In this connection-it is to be noted that' the changes in the wheel dueto temperature changes are small; but if not compensated for it either means large clearances resulting in excessive leakage, especially where the lpressure of the iiuid stream is above that of the casing, or rubbing between -relatively rotating'parts. The central portion may be constructed lto carry all of the buckets, while the detachable portion or portions, as the case may be, act

as protecting devicesonly On the other hand, the detachable portions may each carry I may useone or more rows of buckets. eitheror both constructions in the same tur'- bine, or I may make a wheel with one detachable portion carrying buckets, while the other or others are plain. In the construction specilied the main portion of the wheel is provfrom the nozzle 5.

bers are provided which are located between I the main body of the wheel and the detachable portion or portions. In ad dition to protecting the wheel from temperature changes the detachable portions also serve to strengthen it.

In the'accompanying drawings, which illustrate embodiments of my invention, Figure 1 is a partial view in elevation and section of an elastic-Huid turbine of the Curtis type. Fig. 2 is a partial plan view ofthe same with certain of the parts broken away 'for the purpose of illustration. Fig. 3 is a detail view in section, showing a slight modification; and Fig. l is an enlarged 4view showing the means forattaching the covering to the main body of the wheel. A

1 represents a wheel-shaft that is vertically .disposed and suitably retained by bearings inside of the casing 2. Situated above the casing 2 and bolted thereto is a casing 3, which carries intermediate buckets 4 and a sectionalized expanding-nozzle 5. It may or may not vcarry valves for'regulating the admission of fluid tothe sections of the nozzle.

6 represents the main body of a wheel which is taper-bored to receive the shaft l. At the periphery the body is provided with one or more rows of buckets 7 ,which rotate with respect to the intermediate buckets il. The main body of the wheel is providedwith projections 8, which receive the covering 9, the latter being preferablymade of rolled-steel plate. The

periphery of the plate or covering isprovided with one or more rows of buckets 10, which receive steam or otherelastic fluid directly The coveringv is secured in place by bolts 11 and l2, and between the "body of the bolt andthe coveringv is a small clearance, so that the covering can expand and contract without disturbing the main body portion of the Wheel. Between each ofthe coverings and the main body are one or more Vchambers 13, which may be lilled with air'j or,

if desired, with motive fluid in a more or'less expanded state. In the present illustration the concentric projections` 8 divide the space l between the web of the wheel and the covering into three concentric chambers; but this may be otherwise arranged, if desired. The principal thing is to have chambers in the wheels that are interposed between the covering and the main body portion to prevent the free transfer of heat. I may admit steam or other heated fluid into the chambers to act as a compensating means.

` to the wheel, without, however, causing the latter to he distorted. 19 represents the nozzle, which supplies fluid to the wheel and may be expanding or non-expanding in character. 2O represents the intermediate buckets, which are situated between the wheel-buckets and are supported by the casing 21. The outside of the casing is provided with a covering' 22, of non-conducting material, to prevent the radiation of heat.

In Fig. 4 I have shown one of the means which may be employed for securing the covering to the main body of the wheel. 23 represents the main body of the bolt, which passes through a hole in the covering or plate 9, which is slightly larger in diameter, so that a limited amount of clearance is provided. "I`he head ofthe bolt is preferably countersunk to reduce the rotation losses. rIhe covering, in addition to protecting the main body of the Wheel from the hot steam or other motive fluid, also serves to strengthen it.

In accordance with the provisions of the patent statutes I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I de sire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. A turbine-Wheel comprising a number of separate portions,with means for securing said portions together which permit them to expand kand contract individually.

2. A turbine-wheel comprising a number of separate portions, with bolts extending parallel with the aXis for securing said portions together' which permit them to expand and contract individually.

3. A turbine-wheel comprising a main body portion, buckets carried thereby, a covering which protects the main body from the eifects of the motive fluid, and means for securing the covering in place. which permit the covering to expand and contract without distorting the main body portion.

4C. A turbine-wheel comprising a main body portion, buckets carried thereby, a covering on each side of the main body for protecting` it from temperature changes, and means for securing the coverings to the main bod.,Y and at the same time permitting them to expand and contract without aiiecting said body.

5. A turbine\vheel comprising a main body portion. projections thereon, a covering for the body portion which engages the projections, a chamber between the body and the covering, and attaching means for the covering which permit it to expand and contract without affecting the body portion.

6. A tu rbine-wheel comprising a main body portion, a covering for the side thereof, a chamber formed between the side and the covering, and means for attaching the covering to the body portion, which permit it to expand and contract without ali'ecting the body portion.

7. A tu rbine-wheel comprising a main body portion, a covering therefor, buckets carried by the covering, and means for attaching the covering to the body, which permit it to expand and contract without affecting the body.

8. A turbine-wheel comprising a body portion, a covering for the body, buckets carried thereby, and bolts for attaching' the covering to the body, which permit the two to have slight relative movements to compensate for differences in expansion.

9. A turbine-wheel comprising a main body portion, projections thereon, buckets attached to the body, plates located on opposite sides of the body, which engage the projections,-

chambers formed between the plates and body, and attaching devices which enter the projeetions and hold the plates in place but permit them to expand and contract ii'ulelwndently of the main body.

In witness whereof I have hereunto set my hand this 20th day of July, 190i.

RICHARD II. RICE. fitnessesz DUGALD MCK. McKiLLor, JOHN A. MoMANUs.

IOO 

